EP0880428A1

EP0880428A1 - Aid for a cutting process

Info

Publication number: EP0880428A1
Application number: EP97948690A
Authority: EP
Inventors: Hartmut Bruhm; Hermann BRUNNENGRÄBER
Original assignee: Maschinenfabrik Goebel GmbH
Current assignee: Maschinenfabrik Goebel GmbH
Priority date: 1996-11-23
Filing date: 1997-10-30
Publication date: 1998-12-02
Also published as: ES2123486T1; DE29620431U1; WO1998023419A1

Abstract

In order to prevent adding of tolerances by measuring instruments, it is suggested that a camera (23, 40) providing a visible picture be used.

Description

Cutting device

The proposed invention relates to the field of cutting elastic, mostly web-like material. Such devices often have a guide which is mounted transversely to the running direction of the web-like material in a machine frame or the like, to which a knife can be attached, which is able to cut the web-like material in its running direction. A clamping device is often used to fasten the respective knife in a desired position along the said guide, so that a carriage, slide or the like, which can be moved along the guide, is inserted and fixed on this guide can. In addition, such carriages or the like are often equipped with a switchable coupling device, by means of which a mechanical coupling can take place between the carriage or the like and at least one of the knives in order to move the respective knife into a previously desired position. Such a device is already known, for example, on the basis of German Patent 30 47 976. However, the device described here uses knives which are able to work with a counter knife in each case in order to cut a web-like material into narrower strips. In addition, it is known, for example from German patent specification 10 24 341, to store a so-called upper knife in a corresponding device in such a way that it is optionally able to cooperate with one of several edges of a sleeve-like counter or lower knife.

If a web-like material to be cut is introduced into such a device, then it is necessary to work together for the cutting process Remove the upper and lower knives from each other so that there is enough space to be able to insert the web-like material into the facility in question before starting work. When the actual work process is started, one of the two knives is moved relative to the other, usually the so-called upper knife relative to the so-called lower knife. Care must be taken to ensure that the so-called upper knife can enter those gaps which the lower knife holds ready for this case or for which it is provided with such gaps, grooves or the like in this case. In the course of this so-called adjustment process, it can very easily occur that the respective upper knife does not enter the corresponding groove of the lower knife intended for it, but rather that the upper knife can hit the outer circumference of the lower knife. This means not only an unpleasant interruption of work, but for example also damage to the upper knife, so that this u. U. may no longer be able to cut the material to be cut in the desired manner with the desired care. Further details can be found in the aforementioned prior publications, to which reference is hereby expressly made to supplement the present description.

In particular, if the respective knives are not automatically placed against one another by an operator at the start of work, for example, there is a risk of the knives hitting against one another, which can be attributed, for example, to the fact that all machine parts involved are necessarily manufactured with certain dimensional variations, so-called tolerances . Here it can happen, for example, that certain errors complement each other and the tolerances thus add up in an undesirable manner. Therefore, it grows The aim is to propose a device that helps to avoid damage to the knives when they are turned on. This object is achieved individually or in any combination with the aid of the appended claims and their features. Because of the proposed solution, it is possible to set the knives in question before starting work without human intervention in such a way that they are not damaged during the setting process. In addition, there is a considerable reduction in the time it takes to bring the knives into their mutual position or position before starting work. Further features and advantages result from the following description of an exemplary embodiment. The individual features of the exemplary embodiment can each be implemented individually or in any desired combination with the aid of specialist knowledge of further embodiments of the invention. The proposed solution will now be explained in more detail with reference to an exemplary embodiment schematically depicted in the attached figures, which explains the inventive concept and does not limit it. The exemplary embodiment can also be modified in various ways on the basis of the present suggestion, without leaving the framework defined by the basic idea. In the present context, the figures do not show any essential machine parts that are well known to the person skilled in the art because of a clearer representation. Rather, the figures only show those parts which are necessary for a more detailed explanation of the proposed solution and its advantages.

The individual figures mean:

Fig. 1: side view, partially cut Fig. 2: field of view Fig. 3 side view, partially cut

An elastic web-like material 1 coming from the cutting device 3 comes in the direction of the arrow 2. On its way, the material 1 wraps around the guide rollers 4 and 5 and the lower knife 6, for example. In the direction of view of FIG. 1, several such lower knives can be arranged one behind the other. In the present context, however, it is sufficient to present a single one as an example, since other or further lower knives are analogous to this. Each lower knife 6 has at least one cutting edge 7, but preferably a plurality of cutting edges, for example the further cutting edges 8 and 9. At least one upper knife 10 works together with each lower knife, preferably in such a way that each upper knife 10 is optionally with one of the cutting edges 7 to 9 or the other cutting edges can work together. 1, a plurality of analog upper knives 10 can also be arranged one behind the other. Each upper knife 10 is rotatably mounted on a carriage 12 with the aid of at least one bearing block 11. If desired, the upper knife 10 can also be driven, for which purpose a corresponding motor can be expediently fastened on the carriage 12, for example. 1, several carriages 12 can be arranged one behind the other. Each carriage 12 is displaceable along a guide 13 which is fastened in the machine frame 14 in such a way that the respective carriage 12 can be displaced across its width at right angles to the direction of travel of the material 1 indicated by the arrow 2. Another guide 15 is provided on the machine frame 14 parallel to the guide 13. This guide runs parallel to the guide 13 and carries a carriage 16, which is also parallel to the guide 13 and thus parallel the respective carriage 12 can be moved. In the carriage 16, a motor 17 is fastened, which can drive a gearwheel 18, which in turn can engage a rack 19. The rack 19 is also fastened parallel to the guide 13 in the machine frame 14. In this way, the carriage 16 can be moved along the guide 13 or parallel to it by starting the motor 17, which is equivalent to the fact that the carriage 16 is able to move itself transversely to the direction of travel of the material 1. A pressure medium cylinder 20 or the like, to which a piston rod 21 belongs, is also fastened on the slide 16. When pressure medium is introduced into the pressure medium cylinder 20, the piston rod 21 can be shifted to the right in FIG. 1, so that it is able to move into a

To engage clutch 22 which is attached to the carriage 12. Thus, by exciting the motor 17 and appropriately engaging the piston rod 21 and clutch 22, the carriage 12 and thus the upper knife 10 can be moved transversely across the running direction and thus across the width of the material 1. The material can consist, for example, of paper, plastic, fabric, textiles, foil, metal or the like. A CCD camera 23 is also attached to the carriage 16 in such a way that it is able to cut the so-called cutting point 24 to observe. The CCD camera is, for example, such a camera which scans its field of vision line by line and is able to distribute each line into individual areas, such as such a camera from Honeywell, Regel-Systeme GmbH, Kaiserleystrasse 39, Offenbach am Main,

Germany, which has become known under the name Micro Switch, series HVS 256 or series HVS 270. This camera is fixed and lockable on the carriage 16 in such a way that the picture taken by it Cutting point 24 and a relatively small part of their environment is at least able to detect. This detection field is indicated in FIG. 2, which can be seen from the fact that the cutting edges 7 to 9 and parts of the upper knife 10 appear and become visible in the field of view. In addition, an auxiliary scale 25 appears in the field of view mentioned. This auxiliary scale provides the guarantee that even if a counter 26 connected to the gearwheel 18 should not exactly indicate the respective position of the slide 16, the CCD camera 23 into the

Position is shifted to reorient or correct using the auxiliary scale 25. In this way, the CCD camera can give a correction command to the motor 17 via a corresponding control device in such a way that it is guaranteed in each case that the respective upper knife 10 can enter the so-called cutting groove 27 assigned to the cutting edge 7 without the upper knife 10 or its cutting edge could hit the cutting blade 7, for example its cutting edge 7. In this way, the distances 28 and 29 remain greater than zero in any case, so that the upper knife 10 can certainly dip into the cutting groove 27.

As an auxiliary scale, for example, the widths 30, 31 etc. of the cutting grooves 27 can be made slightly different from one another, so that the CCD camera can register when scanning the cutting grooves how wide the cutting groove just opposite it is. In this way, the result of their scanning can be compared with the result reported by the counter 26. However, since the exact position of the edges of the cutting grooves 27 is known in each case, it is possible to correct the counter 26 or its zero position if necessary. This is advantageous, for example, if the rack 19, for example wise should have become slightly inaccurate due to thermal expansion during operation of the facility.

For the sake of clarity, material 1 is not shown in FIG. 2. In the professional world, the knife that is usually available alone or at relatively large intervals is referred to as the so-called upper knife, whereas the counter knife that works with the upper knife, regardless of whether it contains only one or more usable cutting edges, is usually referred to as the lower knife. This designation also applies if - as in the present case - the so-called lower knife in the figures above and the so-called upper knife in the figures below should be arranged over the width of the material 1, for example only one carriage 16 can be present , which can be coupled with at least one, but preferably a plurality of slides 12 as required. In addition, it is also possible that all of the carriages 12 present in the respective machine device can be coupled and connected to one and the same carriage 16 if necessary. Thus, after appropriate control of the slide 16 - for example with the aid of the motor 17 and the rack 19 - each existing slide 12 can be coupled to or decoupled from one and the same slide 16. In this way it is possible to borrow several knives 10 one after the other to the respectively desired position, so that they can work together with a wide variety of cutting edges of the lower knife 6 in the subsequent machining process. All of the features mentioned and / or illustrated in this description are. essential to the invention, also insofar as they are not expressly claimed in the appended claims. Because of the above suggestions, it is no longer necessary for a person skilled in the art to be inventive in order to carry out further applications or develop areas of application, including his specialist knowledge, if this should prove to be advantageous or even necessary. For example, the slides 12 and 16 can also be designed as carriages with rollers or the like in order to meet the requirements described. The piston rod 21, together with the coupling 22, represents a coupling device. A plurality of slides or the like 16 can also be displaceably provided on the guide 15, which can each be used for optionally coupling into a plurality of slides or the like 12. The proposed device is particularly advantageous when it is not only a matter of first removing the respective upper knife in front of its associated lower knife and then approaching it again. Rather, it is particularly advantageous if the upper knife is first removed from its lower knife, then moved along the guide 13 in order to then be approximated to another lower knife, if a so-called format change is carried out. In addition, the proposed facility is not just for that

Suitable for cutting with circular knives, but also when at least one flat so-called razor blade knife is to interact with the grooves of a corresponding rotating circular lower knife.

In addition to a CCD camera, another device operating in an analog manner can also be used, provided that it is suitable for meeting the stated purpose. However, these other facilities are generally more complex than the one mentioned. The motor 44 can also be indirectly attached to the holder 45. Another more practical and inexpensive option is to install a camera 40 that is capable of providing an ultimately visible image. The electrical ones correspond to the image observed by the camera

Transfer impulses from the camera 40 to a screen 41, so that an image of what the camera observes is formed on the screen. This image can be enlarged compared to its object. The picture itself corresponds to that according to Fig. 2. The control buttons 42 and 43 are assigned to the screen 41, the actuation of which, for example, enables the motor 44 to be rotated in one or its other direction of rotation. The motor 44 is fastened to the holder 45 of the respective upper knife 10 and can rotate a gear 46. The gearwheel 46 engages in a toothed rack 47 or a similar device which is fastened to the housing of the machine device parallel to the geometrical axis of the lower knife 6, for example to the machine frame 14. In this way, an operator can, for example at the control panel of the machine or from another suitable location, observe the position of the upper knife 10 to be observed with respect to its respective position relative to the lower knife 6 and, if necessary, correct it by hand at the push of a button. The camera used for this is, for example, a Micam camera from Digital Vision Technologies, 29 AV Champollion, F-31100 Toulouse. By choosing suitable lenses for this camera it is possible to vary the image section captured by the camera, for example to design it in such a way that the effective position of at least one upper knife 10 and at least two cutting edges of the lower knife 6 is detected. A particularly well visible image results when a light source 48 is positioned on the side of the upper knife 10 opposite the camera 40, in other words the camera 40 is forced to work in the backlight.

In addition, the lower knife 10 and its holder 45 can also be fastened to the slide 16 and displaceable relative to it within certain limits. The movement of the camera and slide takes place essentially and preferably in the direction of the geometric axes of the lower and upper knife or at least parallel to these.

Parts list

1 material 30 width

2 arrow 31 width

3 cutter 40 camera 4 guide roller 41 screen

5 guide roller 42 control button

6 lower knife 43 control button

7 cutting edge 44 motor

8 cutting edge 45 holder 9 cutting edge 46 gear

10 upper knives 47 racks

11 bearing block 48 light source

12 sledges

13 Guide 14 machine frame

15 leadership

16 sledges

17 engine

18 gear 19 rack

20 pressure cylinder

21 piston rod

22 clutch

23 CCD camera 24 cutting point

25 auxiliary scale

26 counters

27 cutting groove

28 distance 29 distance

Claims

Expectations

1. Device for cutting elastic web-like material (1) with at least one guide (13) running transversely to the running direction of the web-like material (1) for at least one knife (10) cutting the web-like material (1) in its running direction, with at least one Clamping device for fastening each knife (10) in at least one selectable position along the guide (13) and an adjusting device with a carriage, slide or the like (16), which is parallel to the knife guide (13) by means of a drive device (17) ) is movable transversely to the direction of travel of the web-like material (1) and contains a switchable coupling device (21, 22), by means of which a mechanical coupling between the carriage, carriage or the like (16) and at least one knife (10) can be produced to move it into a selectable position and with a camera (23) attached to the carriage, carriage or the like (16) such that at least the cutting edges (7 to 9) at least one upper knife (10) and at least one lower knife (6) can be observed by the camera (23), characterized by a camera (40) that is effectively connected to a screen (41) and provides a visible image.

2. Device according to claim 1, characterized by at least two cutting edges of a lower knife (6) and an effective position egg Nes upper knife (10) representing image section of the camera (40).

3. Device according to claims 1 and 2, characterized in that the image displayed by the screen (41) is larger than the object observed by the camera (40).